Electronics and Communication Engineering - Digital Electronics - Discussion

Here is the Trick to find 2's complement.

Write the number as it is until you find the "one" after the one apply one's complement.

Example 1:
The number is 11010101 we need to find the 2's complement so find the (Start on left side) in this number the first number is one so write as it is after the one we will apply one's complement.

Ans: 00101011 this is the 2's complement.

Another example;
11010100 here the first number is zero write as it is until you find one after one apply one's complement.

00101100 This is the 2's complement of this number.

We have to follow 2 steps to find out the 2's complement.
1.find out 1's complement for the given num.
(0's becomes 1's and 1's become 0's)
2.Add 1 to the result of 1's complement.
So,(1) 1's complement of 0101 becomes 1010.
(2)add 1 to this result,

1010(1's complement)
1 (adding of 1)
---------------
1011. (2's complement).
It is the final answer..

1's complement is nothing but change all bit invert.

For example 1'complement of 1 is 0,1'complement of 0 is 1

Step1:
Here 1'complement of 0101 is 1010.

2'complement is nothing but add 1 with 1'complement.

1010 + 1 = 1011.

Answer: A.
2's complement = 1's complement+1.
1's complement means take the complement of given data.like given data is 0101 = 1010.
Next 1 should be added to that complement.

1010
1
........
1011

So option A correct.

2's complement means last number is subtract by 2 then the other numbers are subtracted by 1.

OTHER WAY TO FIND THE 2'S COMPLEMENT:
1. Take 1's complement.
2. And add 1 with that 1's complement answer.

@Bharathy.

Put complement one time for every bit (replace 0 by 1 and 1 by 0).

That means 1's complement of 0101 is 1010.

0101.

1's complement is 1010.
Add 1 to 1's complement is called 2's complement.
i.e.,1010+1=1011.

How to find 1's complement? please help me.

What is 2's complement? Explain please.

2's complement = 1's complement + 1.